Heart murmur causes discomfort and unwanted anxiety. There are a few causes of heart murmurs that can range from serious to non-threatening—either way, It is wise to understand the cause of a heart murmur.
- Heart murmur due to fever. In infants and older people the most common cause of a heart murmur is fever. Fever causes raised heartbeat. The heart works over time and the pressure of blood in vessels increases. This increased pressure causes a rushing sound from the chest area. This is not dangerous and goes away as soon as the fever subsides.
- Thin chest wall. One of the most common reasons is a birth defect in which the chest wall is not thick enough. The organ placement is too close to the chest wall. This makes heart functions become more audible and thus a heart murmur is heard.
- Venous hum. As the name suggests, this is a soft humming sound that is heard in some infants. The neck veins are larger in diameter, so when blood flows through, a gushing occurs. This flow of blood from narrow veins to wider ones produces a humming sound. This heart murmur however is not dangerous and with the growth of body it gradually disappears. In some people who are physically weak, this humming can still be heard after they are adults.
- Valve Stenosis. This is a condition in which a valve of the heart becomes narrow. In children this can be a birth defect whereas in older people there can be a couple of reasons. Smoking and hypertension are the main factors in causing narrowed valves. As the heart has to pump harder and the blood has to push with force to squeeze through, a strained sound, or murmur, is heard. This is case that requires immediate medical attention.
- A regurgitating valve. This condition occurs when the flaps that stop blood from flowing freely into other valves start to malfunction. This means the flaps do not close or are unable to close completely, allowing blood to leak into the other valve. This disrupts the hearts natural function and can prove fatal at times. Heart murmur caused by this defect should not be left untreated.
- Septal defect. The most dangerous cause of a heart murmur is a Septal defect. This is a birth defect in which the heart has a small or large hole. This alters the blood pressure. The blood tends to flow from pressure concentration area to low pressure areas. A loud murmur is usually less fatal because it shows the presence of a small hole. Larger holes cause a faint heart murmur because the blood flows easily. This needs immediate surgical treatment.